HLS
HLS
Intro
Every HLS file has these properties
#EXTM3U
#EXT-X-VERSION:4
HLS Playlist Types
De-Muxed | Muxing
Test Streams
developer.apple.com/streaming/examples/
dash: 'https://cdn.bitmovin.com/content/assets/sintel/sintel.mpd'
hls:'https://cdn.bitmovin.com/content/assets/sintel/hls/playlist.m3u'
Apple HLS examples - bib bop advance HEVC
Apple HLS examples - Multiple audio and subtitles
Apple HLS examples - bib bop normal
HLS stream having :
. 6 video qualities for Adaptive Bitrate
. 2 alternate audio tracks (English and French)
. 3 alternate subtitle tracks (English, English with audio description and French)
Link
Spatial 3D HLS
historic_planet_content 3D video
HLS Keys
TARGET DURATION
This sets the playlist or the video processor that all the components .mp4 or .ts or segments of audio/video/text are of specific secs. In this example the target segments are of 10 secs each.
#EXT-X-TARGETDURATION:10
#EXTINF:10.0,
fileSequenceA.ts
#EXTINF:10.0,
fileSequenceB.ts
So if the targetDuration is higher then the avPlayer library would take some time to buffer first 2 - 3 fragments and then resume.
So 10 secs * 2 so 20 secs of content. This is what I assume I understand from my conversation about this.
CONTENT METADATA
Protocol HLSTagDescriptor and HLSTagValueIdentifier
HLSTagDescriptor = EXT-X-XCAL-CONTENTMETADATA | the tag name
HLSValueIdentifier = KEYID | DRMAGNOSTIC | the attribute names in the tag
#EXT-X-XCAL-CONTENTMETADATA:KEYID="bd8e7d69-saw4-6a00-1eb9-637364ad6a4c",DRMAGNOSTIC="ZXlKNE5YUWpVekksa3r3XXzNFTnZrSFE="
Techniques
Switch Live to Event Record
When I think of an EVENT style playlist in streaming world, I think of DVR | Video Recordings. If a user is scrolling the Live Grid in video stream app and they want to record an episode, that playlist will go from LIVE -> EVENT. Best way to see this is to select a live program, hit Record, wait until the UI says the recording is set. Next, hit Watch and you'll see the Live HLS manifest file program is now Event
Thumbnails
#EXT-NOM-I-FRAME-DISTANCE
Advertising
#EXT-X-ADVERTISING:SYSCODE=231532523532377442
DRM
#EXT-X-XCAL-CONTENTMETADATA:
KEYID="017ee539-UUID-string",
DRMAGNOSTIC="some_base_64_key_value"
Apple Interstitials
Getting Started With HLS Interstitials - apple developer
Other
References
what-is-hls-video-streaming-and-how-does-it-work
hls-http-live-streaming-how-does-it-work
what-is-hls-streaming-and-how-do-you-deploy-it
apple developer | doc archive | HLS Overview
Specifications
HLS content steering | apple specs
Highest quality
video - 0 = is the highest quality in the HLS format.
Playback
Tools
This gives us a debug analysis of the stream in question to validate whether its a stream issue or our player code issue.
mediastreamvalidator https://314.linear-ag-xcr/v1/frag/bmff/enc/wea/t/OsaK_UD_T_7381_0_7683.m3u8`